How far is it altogether? 150 miles? If you can be sure of getting a charge when you reach your destination, maybe you don't need to plan to stop.
I'm planning my first long motorway trip for Tuesday, to avoid the Bank Holiday rush. I'm going from West Linton in Peeblesshire to Halifax in Yorkshire, which I know is about 195 miles. I have no intention whatsoever of trying to do this on one charge in the SR, it would be insanity. Given that I'm going to stop once, I checked the motorway service stations to formulate a plan.
The nearest one to half way is Southwaite, 88 miles from home, and there really isn't any point in stopping sooner than that. That is my planned charging stop, which will leave me 107 miles to go. I imagine that's what will happen - I'll find an ultra-rapid charger, leave the car, have a coffee and a scone or something, read my Kindle, and get back to a fully-charged car that will easily do the rest.
However, if there is a problem at Southwaite, the next service station, Tebay, is definitely a problem, because at the moment it only has Tesla chargers. (I'm told that chargers for the hoi polloi will be open in the summer, so subsequent trips will be able to include that one.) There is apparently the possibility at the moment of using an access road to get to the northbound service station, which has ordinary chargers, so that's a possibility. There is also a single rapid charger in Tebay village itself, which is easily accessed from the motorway. Right now I intend to skip Tebay unless my charge level is worrying (in which case I should probably have made my first stop at Gretna Green or Todhills and be thinking about a second stop at Kirkby Lonsdale, but I doubt that will be necessary).
Backup is therefore Killington Lake, at 128 miles, which should still be fine. I really doubt that both Southwaite and Killington Lake will be problematic, but as this is my first foray I'm covering all the bases. Second backup is Kirkby Lonsdale, at 140 miles. That should be doable at this time of year, although I'd be a bit nervous about it in the depths of winter.
In the highly unlikely event of all three options being unavailable, I will not leave Kirkby Lonsdale without a charge, come hell or high water. There isn't a lot after that until Skipton and I would not be comfortable going on. I think the consequences of running out of charge in an EV are serious enough that I would not be prepared to risk it. It's not as if rescue is only a can of petrol away.
Once I get to Halifax, the fates (and Calderdale Council) have erected a few type 2 charging stations right opposite my friend's house. They're expensive, but for a few days I don't mind. So I'll just leave the car on one of these overnight, and I'll be all set to show off the car's performance the next day. This will also let me leave with a full charge when I set off home. (I will also take the granny charger so I can charge at my friend's house itself in case of any problem with the type 2s.)
On the way back I have the same system. Preferred charging stop is Southwaite again, 104 miles away, and 88 miles from home. (If I'm eating charge, Tebay at only 78 miles is also a possibility on the north-bound carriageway.) Backup stops are then Todhills (117 miles, 78 miles from home) and Gretna Green (124 miles, 72 miles from home).
This is undoubtedly overkill bordering on the obsessive, but it will be my first trip and I don't want to be caught out. I expect that once I've done a few of these I'll be quite relaxed and take it in my stride.
I had a serious range anxiety issue in my Peugeot on that road, driving north, on Christmas Eve some years ago. I knew I was quite low on petrol when I started, but was rashly confident of getting the stuff on the way. I passed a couple of open petrol stations in Halifax itself, but didn't stop. Silly me. I don't remember why I didn't stop in Keighley, or maybe the early-closing problem had already caught up with me by then. I remember driving round Skipton and finding two petrol stations, both closed early for the night. The one at Hellifield had ceased operations entirely.
I kept going, trying to drive steadily at about 50 mph with a light right foot. The Co-op petrol station at Ingleby was closed. I was pinning all my hopes on Kirkby Lonsdale by then, and when it was closed too I started to panic. I was very reluctant to turn on to the M6 when I knew I was running on fumes. Killington Lake is southbound-only and the next one up is Tebay which I didn't have a hope in hell of reaching. Going south, Burton in Kendal is only six miles away - but it's northbound-only! I phoned the RAC to be told that they would only come to rescue me if I had actually run out, and no they had no idea what I should do other than go on until the car conked out.
In the end I turned south for Burton-in-Kendal, but on back roads, not on the motorway. I made it to the northbound service station by dint of going down an access road against a no-entry sign, and I haven't seen anything quite so welcome as that row of petrol pumps. It was quite late on Christmas Eve by then, but of course the motorway services never close. The absolutely lovely girl at the cash register gave me a box of mince pies her mother had made - she was giving them to all the travellers who stopped there that night, as a Christmas gift. I could have kissed her.
That was bad enough, but if the worst had happened I'd simply have had to sit it out in the car until the RAC brought me a can of petrol. Not going even close to there in an EV.
